RAdio Detection And Ranging (radar) can be used in many applications including object detection, range-finding, direction-finding and mapping. Traditionally, radar has been used in aerial vehicles, satellites, and maritime vessels to locate objects and image terrain. In recent years, radar is finding increasing use in automobiles for applications such as blind-spot detection, collision avoidance, and autonomous driving. Unlike optical-based sensors (such as cameras or Light Detection and Ranging (LIDAR) systems) which are affected by changing weather and visibility, radar is capable of functioning in low light conditions, in the dark, and under all types of weather conditions.
However, existing automotive radar technology may lack the required resolution to (1) sense different objects, (2) distinguish between closely spaced objects, or (3) detect characteristics of objects on the road or in the surrounding environment. The resolution of existing automotive radar systems may be limited in both azimuth and elevation. Additionally, existing automotive radar systems tend to have a limited number of antennas and/or antenna channels, and limited aperture size due to constraints imposed by automotive vehicle body size.
To improve angular resolution, some detection systems may use multiple antennas. Such systems may need a large number of antennas spaced apart at a certain distance in order to achieve improved angular resolution. However, such systems often require additional components and sensors that are cost prohibitive for commercial automotive use. Furthermore, the total physical size of such systems may make it impractical to implement such systems on terrestrial vehicles.
With the recent emphasis on autonomous driving, there is a need for long range detection systems on automotive vehicles that can provide advance notice to drivers about potential obstacles or dangers on the roads. However, existing automotive radar technology may not be ready and/or suitable for deployment in long range detection systems on automotive vehicles, in view of at least the challenges described above.